Robotic systems to date have produced primarily machines that bear little resemblance to human beings. Part of the reason for non-humanoid approaches to robot builds is the difficulty in replicating human balance and coordination in machine language that is translated into mechanical movement. For example, with few exceptions, robots typically employ quadruped or track systems to move. It has been a difficult challenge to construct quadruped systems that can maintain balance while walking. The internal elements, (for example, support bars, hydraulic systems, pneumatic systems, etc.) have been difficult to coordinate between the upper robot halves and the legs. Coordination is often a product of insufficient programming that is not seen until live testing.
Currently, simulation software predicts a desired movement rather than actual performance between robot elements. This can be an expensive approach since once the build is started, troubleshooting may result in costly redesigns of robot features.
The result has been robots that appear more mechanical than humanoid. While some recent attempts have produced humanoid looking features on robots, the challenges with movement and coordination persist.
In addition, there have been many challenges to constructing robots with artificial muscles that can replicate humanoid movement. Currently robots can produce either fast twitch or slow twitch movements but not both in coordination. One of the challenges lies in the design of artificial muscles. For example, some robots use pure hydraulic cable systems which provide linear movement unlike human movement. Examples can be seen on factory floor assembly lines. Other robots use artificial muscles based on electro-active polymer casings that are actuated by applying an electric field to the casing. While such an approach may work for an individual artificial muscle, a negative phenomenon is observed when such artificial muscles are positioned in abutment as real muscles would be in a muscular system. The electric field applied to electro-active casings creates a spillover effect onto adjacent artificial muscles. As a result, electromagnetic interference may be observed causing the artificial muscles to operate out of sync with adjacent muscles and or fail altogether because the electric field signal applied is negated. Moreover, artificial muscles relying purely on electro-active polymer casings suffer from fatigue and being overloaded easily by heavy loads because the polymers have relatively low tensile strength.
As can be seen, there is a need for a robot that moves and appears humanoid and for a process to predict the performance of robots accurately.